A known bolted pilot web is found in U.S. Pat. No. 4,004,472. This patent describes a detachable bearing support secured to a housing by a series of bolts. The bearing support is made from cast iron to ensure that the inner bearing assembly does not work loose during operation of the differential unit. The bearing support is detachable in order to provide a method for mounting the drive pinion in the housing.
U.S. Pat. No. 6,544,140 provides a pinion mounting comprising a race attached to the casing of the differential gear mechanism by a plurality of bolts. The bolts are installed through a plurality of mounting holes in the radial flange of the race. The race is in constant contact with the casing, resulting in no gap therebetween.
The above-described designs have several disadvantages. Known heavy and single tandem axle designs include the integration of the pinion bearing cage into the carrier casting. Because of the relative shape and position of the pilot web relative to the remainder of the carrier assembly, casting the carrier as a single piece is more complex and not a cost effective casting process. Attempts at bolting the pilot web to the remainder of the carrier assembly have resulted in unacceptable transference of forces, and the bolts coming loose under load.